The Commissioners who were appointed in 1833, were re-appointed under the Act of the 2d of May, 1834. They immediately entered upon the duties of their office, thoroughly re-examined their former work, and decided that the Croton River was the only source that would furnish an adequate supply of water for present and future purposes. In making these examinations they employed, as Engineers, David B. Douglass, John Martineau and George W. Cartwright, Esquires. Various plans were proposed for conveying the water to the city, and estimates made of the cost of the work constructed by either of these plans, but the one recommended by the Commissioners, and that for which a preference was expressed by the Engineers, Messrs. Martineau and Douglass, was a closed Aqueduct of masonry. These gentlemen each made an estimate of the cost of bringing the water of the Croton River to the city of New-York by a closed Aqueduct of masonry, and the Water Commissioners offered, as the true cost of the work, an average of the two estimates. The cost of the work, as estimated for this plan and presented by the Water Commissioners, (including the cost of the city mains and conduits,) was $5,412,336.72. The report of the Water Commissioners was referred to a Committee, who reported to the Common Council, on the 4th of March, 1835, two resolutions, the first approving the plan adopted by the Commissioners as described in their report; and the second referring the subject to the electors at the ensuing annual election, as required by the Act of May 2d, 1834. These resolutions were adopted by the Common Council, and at the election in April, 1835, the subject having been duly submitted to the electors of the city and county of New-York, a majority of the voters were found to be in favor of the measure. On the 7th of May following, the Common Council “instructed the Commissioners to proceed with the work.” Thus authorized, the Commissioners immediately commenced the preparatory measures for the construction of the work. David B. Douglass was employed as Chief Engineer; he proceeded in the location of the line for the Aqueduct and in preparing plans, until October, 1836, when he was succeeded by John B. Jervis, who continued at the head of that department during the construction of the Aqueduct. The construction of the work was commenced in May 1837; and on the 22d June, 1842, the Aqueduct received the water from the Fountain Reservoir on the Croton:--on the 27th of June, the water having been permitted to traverse the entire length of the Aqueduct, entered the Receiving Reservoir at the city of New-York, and was admitted into the Distributing Reservoir on the 4th of July.